PURPOSE: To shorten bundled wirings, to easily treat the bundled wirings and to reduce a storage space of the wirings by engaging protrusions of both sides of a printed board with a connector with holes formed at two printed boards, and temporarily securing the board with the connector at a front panel side.

CONSTITUTION: Square holes 17 to be engaged with protrusions 16a at the corners of both sides of a printed board 16 with a connector are formed at the ends of printed boards 13, 14, the protrusions 16a are engaged with the holes 17 in a state that the board 16 with the connector is disposed between the ends of the boards 13, 14, and the board 16 with the connector is temporarily secured. The boards 13, 14 are connected to the board 16 with the connector via bundled wirings 18. A back panel 12 is associated with a front panel 11 in this state to assemble a sheathed housing, and the board 16 with the connector is clamped with a screw 19 from outside the panel 12. Thus, the wirings 18 are shortened, the treatment of the wirings 18 is facilitated, and the storage space of the wirings 18 is reduced.